Pipe slip



. 1,630,732 y 1927' w, D. DAVIDSON PIPE SLIP Filed March 29, 1924 2Sheets-Sheet 1 ?Zw *Z M y 1927' w. D. DAVIDSON PIPE SLIP Filed March 29.1924 2 Sheets-Sheet 2 Patented May 3 1, 1927.

UNITED STATES) PATENT oFF WILLIAM D. DAVIDSON, or Los 'ANGELES,CALIFORNIA, ASSIGNOR, BY ME'sNn ICE.

SIIGNMENTS, .OF ONE-HALF T0 EMSCO DERR ICK & EQUIPMENT COMPANY, OF LOSANGELES, CALIFORNIA, A' CORPORATION TITUSVILLE FORGE COMPANY,orTI'rUsvILLE, PENNSYLVANIA, a CORPORATION or MARYLAND.

OF CALIFORNIA, AND ONE-HALF TO- PIPE BL P.

Application filed March 29, 1924. Serial No. 702,804.

' mg andmaintaining oil Wells. In these arts it is necessary to place,remove, orsuspendpipe in the well. It is often necessary, duringoperations on the well, to prov de a temporary support for the pipentermediate of the collars thereon- This can conveniently beaccomplished by providlng a supporting ring, having a conoidal holetherein somewhat larger than the pipe,

which passes therethroiigh'and'which it is desired to support, thelarger diameter of the conoidal hole being upward.

Inthis holemay be placed curved'wedges, commonly called slips, the innersurface of these slips being cylindrical and provided with teeth toengage the pipe, and the outer surfaces being conoidal and of a shape tocooperate with. the conoidal hole in the supporting ring to -force theslips inwardly as thev weight .of the pipe is shifted thereto and theslips are pulled downwardly.

It. is desirable that the collapsing action of the slips on the pipe beexerted uni;- formly about the periphery of the. pipe, so that the pipeWill not be forced permanently out of itstrue cylindrical form, and itistherefore desirable to make the slips in more than two segments. Atthe same time, since the slips must be quickly and simultaneouslyplaced, even where there are only three men in the derrick, and since itis necessa under ordinary conditions, to have eac slip handled by adifferent man, it is necessary to keep the number of separate sli sbelowfour and. preferably below three. t is not uncommon, however,'to seethree part slips in use, these. slips requiring three men to place themin addition to the fourth'man who controls the hoisting apparatus, fromwhich the pipe is suspended.

It is an-object of my invention to provide a four iece slip -whichcan'be place by two men. uch a 'slip is more desirable than the commonthree p1eceslip,in that it re-.

by the line 33 of Fig. 2.

- of said table.

Slips 18 are pivoting a pivot pin for each pair. My in-' vention(litters from-such previous attempts,

a pivot pin for each slip Fig. 2 is a section on an. enlargedscalethrough oneform of slips, on a plane represented by the line 2-2 ofFig. 1.

Fig. 3 is a section on a plane'represented Fig. 4 is an elevation of theing handle arrangement. j

In the form of the invention illustrated, 11 is the pipe which it isdesired to support. This pipe passes through a hole 12 in a supportingring 13. This ring may form a part of the rotary table or it' may bepart of an elevator supported independently The hole 12 is provided witha tapered upper portion 14 having a larger slips, showdiameter at the,top than at the bottom.

provided fitting in the tapered portion 14 ofthe hole 12, these slipshaving a tapered outer surface 15. and an inner cylindrical portion 16,which ispreferably provided with teeth 17 to enable the slip to moretightly grip the ipe. The slips are preferably formed in our sections,as shown in Fig. 2, each section being provided Withrecesses 20- andwith a vertically extending pivotjpin 21. A

The recesses 20, in'which the links 22- link 22 is placed iheach of therecesses 20, thepivot pins 21 i projecting cars 31 are provided on eachof theslips l8 and a common handle 35 is provided, this handle having aroller 36 rorrned thereon. This allows each pair of slips to be handledas a unit so that only two men are required in addition to .the man atthe hoisting apparatus.

One of these men stands on one side of the pipe and the other man standson the other side, and at a signal from the operator of the hoistingapparatus, they place the slips 18- simultaneously in the holes, 12. Theoperator then lowers the pipe 11. The teeth 17 engage the pipe and theWeight of the pipe tends to force the slips downwardly and inwardly intocontact With the surface of the pipe. By providing four slips, I am ableto provide for a very uniform pressure around the periphery of the pipeand by providing the two pivotpins 21 and the links 22, I am able toallow for an. individual adjustment of each slip to suit anyirregularities in the pipe.

I claim as my invention: 7

1. In a gripping device of the character described: a pair of slipshaving pairs of recesses extending inwardly from their outer sides, therecesses of each slip being spaced from each other and from the upperand lower ends of the slip, each pair of recesses being adapted toreceive a link crosswise; said links lying on the bottoms of said pairsof, recesses; a vertical'pin in each of said slips, said pins extendingthrough said links to hingedly connect said slips; and common meansindependent of said pinsfor holding said 'slips, said pins being quicklyre- WILLIAM DAVIDSON.

